Time for another training session, and this time with my new Tacx HRM. The Bluetooth connection worked and as I set-off for training session 6, I was starting to feel more confident in the success of my project. I kept the watts steady through the warm-up 8 minutes, ramping things up for the medium exertion, and like last time, I found the going tough. As I ramped up for the 4 minutes at 200 watts, nothing happened on the watts read-out, so I put the bike into the hardest gear and upped my cadence to 120 RPM. It was absolutely exhausting and still the watts were showing values of around 150. Only then did I realize that it wasn’t my performance that was at fault, but that there must be something wrong with the bike set-up. I don’t often fall into the ‘trough of despondency’, but I was finding it difficult to keep a level head.
I suspected that it was something to do with the position of the wheel on the roller, and I noticed that it had moved to a slightly off-centre position over the last couple of sessions, so I re-mounted the bike (with the help of the Scotland Lonely Planet Guide under the back wheel) to a central position and re-tried it. I managed to get the watts comfortably over 200 watts and did a max power test to over 600 watts. Problem solved for now, I hoped. I made sure the locking nut was as tight as possible, as I think that had added to movement of the back wheel.
Summary of trials, tribulations & delights:
Post-script: There is possibly an additional reason why the watts values are spurious for this training session, which I am still trying to understand. I chose heart- rate and not slope from the Training App main menu, so the trainer was possibly trying to keep my heart rate below 180 bpm by automatically adjusting the break resistance. A mystery as yet un-solved.